CANADIAN JERBOA. 
737 
appear sunk in its gelatinous surface; those along the back and 
belly are of an oblong oval form, and close set together ; and in other 
parts they are round and more distinct. Both the parts are mottled 
with small white spots, and have two distinct lines composed of small 
white streaks, continued along from the feet to the tail. The fin of 
the tail has no rays, and is no more than an adipose membrane like 
that of the eel. 
Dr. Garden, in a letter to Mr. Ellis, mentions a remarkable 
property of this animal; viz. that his servant endeavouring to kill 
one of those by dashing it against the stones, it broke into three or 
four pieces. Linnaeus, from the description sent to him, made it a new 
genus called Siren, of a new order Meantes, of the class Amphibia. 
But from this class, both the order Meantes, and that of Nantes, have 
been lately expunged, and Gmelin had reduced the Siren to a species of 
Muraena. Its place here, however, seems still of doubtful propriety, 
as Gmelin himself acknowledges in the preface to his Systema Natu- 
rae ; for, Campfer, having dissected the Siren, discovered that on 
each side of the head it is furnished with three true gills, separated 
from each other by membranes having teeth-iike append ages ; that 
the mouth is armed with strong and firmly planted teeth ; that the 
heart has only one ventricle ; and that the abdomen is filled with 
very long and capacious intestines : from all these circumstances, he 
concludes that this animal ought to be considered as a fish of the 
order of Branchiostegi ; while in other respects it is more nearly 
allied to the genus Muraena, of the order Apodes ; although it dilfers 
materially from the other species of that genus, by having only three 
notched bones in the gills, and from the pectoral fins being each divi- 
ded into four finger-like appendages. 
Canadian Jerboa. 
This animal is thus described by general Davis. ‘'As I conceive 
there are very few persons, however conversant in natural history, 
who may have seen or known that there was an animal existing in the 
coldest parts of Canada, of the same genus with the jerboa, hitherto 
confined to the warmest climates of Africa, I take the liberty of 
stating the following particulars. With respect to the food, or mode 
of feeding, of this animal, I have it not in my power to speak with 
any degree of certainty, as I could by no means procure any kind of 
sustenance that could induce it to eat; therefore, when caught, it 
lived only a day and a half. The first I was so fortunate as to catch, 
was taken in a large field near the fall of Montmorena, and by its 
having strayed too far from the skirts of the wood, allowed myself, 
assisted by three other gentlemen, to surround it, and after an hopr’s 
hard chase to get it unhurt, though not before it was thoroughly 
fatigued, which might in a great measure accelerate its death. 
“ During the time the animal remained in its usual vigour, its agility 
was incredible for so small a creature. It always took progressive 
leaps of from three to four, and sometimes of five yards, although 
seldom above twelve or fourteen inches from the surface of the grass ; 
but I have frequently observed others, in shrubby places, and in the 
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